Foldover condiment package film

ABSTRACT

Foldover squeeze packages for containing flowable material generally have a first sidewall and a second sidewall that are sealed to each other around their respective perimeters. The second sidewall has an outlet that permits the flowable material to exit the package. A portion or flap of the package is folded over and sealed directly to itself around the outlet. Films for forming such foldover squeeze packages include a first film and a second film. The second film has at least first and second layers, wherein the second layer is adapted for use as an interior surface of a second sidewall a squeeze package and the second layer is adapted to seal to itself without disrupting the seal between the sidewalls of the package.

TECHNICAL FIELD

[0001] The present invention relates to films for forming foldoversqueeze packages. More particularly, the inventive films are capable offorming a package that is folded over and sealed to itself around anoutlet for the contents of the package.

BACKGROUND OF THE INVENTION

[0002] Various attempts have been made to provide a dispenser package inwhich a flowable product may be packaged in the quantity normallyrequired for single or multiple uses, and from which the containedproduct may be dispensed. One type of such dispenser packages is apillow package or sachet, typically made of relatively thin plastics andfoils or combinations of laminated plastics and foils. These packagesare most frequently encountered as containers for catsup, mustard, othercondiments, homecare preparations such as hair conditioners, dyes andcremes.

[0003] Although this type of package is universally used, it is oftendifficult to access the contents of the package. To obtain access to thecontents, the package must be held in one hand while a tearing motionand force are applied by the other hand. Creating the initial tear tobreak the package's seal can be difficult, often requiring theassistance of the user's teeth. Moreover, once the initial tear iscreated, the laminated foil and/or plastic material often tears in anuncontrolled fashion. In addition, the holding pressure exerted by oneof the user's hands often forces the contents out of the envelope notonly before the user is ready to apply the contents, but even before thetearing motion is complete.

[0004] The user must also use both hands to open the container. In thecase of invalids, arthritis sufferers and other handicapped people,opening these packages is virtually impossible. Further disadvantagesinclude the package's inability to function effectively with lowviscosity products such as coffee cream, mouthwash or alcoholicbeverages, due to the inability of the torn opening to control thedirection of flow of such liquids from the package. These packages alsoare generally totally unrecyclable, and therefore become environmentalpollutants. As above-mentioned however, should continued use of thesepackages be preferred, then the easy opening feature of this applicationmay be readily and economically adhered to the package to make for aneasy opening, reclosable, high-barrier package.

[0005] An easy to open package is disclosed in U.S. Patent PublicationNo. 2001/0030192 filed by Redmond, which is hereby incorporated byreference. The package disclosed in Redmond is a foldover squeezepackage that can be sealed or adhesively attached over a small pre-madeoutlet aperture. The package may be made of polypropylene, high-densitypolyethylene, PVC or polyester. However, the package may requireadhesive to seal the package to the outlet aperture which adds to theexpense of manufacturing the package. Also, if adhesive is applied inthe incorrect location on the film, the film may be incapable of foldingover and sealing to itself.

[0006] Alternatively, the package may seal directly to itself withoutadhesive. However, the temperature required to seal the package toitself is too high, the heat can disrupt the seal between the sidewallsor cause the interior walls of the package to seal together. Therefore,what is needed are films capable of forming a package similar to thepackage disclosed in Redmond and forming a peelable seal withoutadhesive at a temperature that does not disrupt the integrity of thepackage.

SUMMARY OF THE INVENTION

[0007] It is an object of the present invention to provide films thatare capable of forming a foldover squeeze package without the use ofadhesive between the flap of the package and the package sidewall.

[0008] It is a further object of the present invention to provide filmsthat are capable sealing together to provide two sidewalls of a package.

[0009] Additionally it is an object of the present invention to providefilms capable of forming a package that when folded over itself, canseal to itself, providing a peelable seal without disrupting theintegrity of the package.

[0010] Additionally, it is an object of the present invention to providefilms that form a package with a sidewall capable of sealing to itself,providing a peelable seal that is adapted to be weak enough to bemanually pulled apart but sufficiently strong to remain closed duringshipping and storage.

[0011] The films are adapted to form a foldover squeeze package withoutthe use of adhesive. The foldover package is designed to contain aflowable material and to dispense the material in a controlled fashion.The foldover squeeze package has an outlet which dispenses the flowablematerial in a controlled fashion. Before opening, the outlet is sealedby a portion or flap of the package which has been folded over andsealed around the package. When access to the contents is desired, theconsumer lifts the flap, automatically exposing the outlet.

[0012] The films of the present invention are capable of forming such aneasy to open squeeze package without requiring localized adhesive toseal the flap around the outlet. The packages may be formed on highspeed production equipment that typically forms several packages acrossa given width of film. The packages are formed and filled in lanes.

[0013] The packages have a first sidewall and a second sidewall that aresealed together around their perimeters. The second sidewall defines anoutlet, such as an aperture or a series of perforations formed in thesidewall. The package is folded over itself and the second sidewall issealed directly to itself around the outlet. The second sidewall iscapable of heat sealing to itself in a peelable seal that allows thepackage to be manually unfolded, automatically exposing the outlet. If aseries of perforations is used to form the outlet, unfolding the packagewill automatically tear the second sidewall at the perforations,creating an aperture.

[0014] The first sidewall is formed of a first film with an inner skinlayer that faces the interior of the package. The second sidewall isformed of a second film with an inner skin layer that faces the interiorof the package. The inner skin layers are capable of being sealed toeach other in a permanent seal to form the sidewalls. The inner skinlayers are formed of materials such as ionomer, low density polyethylene(LDPE), linear low density polyethylene (LLPDE), linear medium densitypolyethylene (LMDPE), metallocene polyethylene (mPE), or blends thereof.Alternatively, the inner skin layers may be formed of any copolymer ofpolypropylene or polyester.

[0015] The second film has a composition that provides an exterior skinlayer capable of sealing directly to itself providing a peelable seal.The composition of the exterior skin layer enables the exterior skinlayer to form a peelable seal at a temperature lower than thetemperature at which the sidewalls are sealed together. In oneembodiment, the exterior skin layer has a sealing temperature of atleast about 8° F. (4° C.) less than the sealing temperature of thematerial in the inner skin layers. In another embodiment, the exteriorskin layer composition has a sealing temperature that is at least about30° F. to about 100° F. less than the sealing temperature of thematerial in the inner layers. Because of this temperature difference,the peelable seal may be created without disrupting the seal between thesidewalls. The peelable seal is sufficiently weak to be pulled apartmanually, but is sufficiently strong to withstand shipping and storagewithout opening.

[0016] As mentioned above, the exterior skin layer is formed of amaterial capable of sealing at a lower temperature than the material inthe inner skin layers. Suitable examples of materials for the exteriorskin layer include ionomer, polypropylene, ethylene vinyl acetate,linear low density polyethylene, low density polyethylene, ethyleneacrylic acid, ethylene methacrylic acid copolymer, metallocenepolyethylene or blends thereof. If the exterior skin layer of the secondfilm and the inner skin layers of the film are of the same type ofpolymer, the polymer of the exterior skin layer is selected to have alower melt point, and, thus a lower sealing temperature, than thematerial in the inner skin layers. For example, ionomer resin may beused in both the exterior skin layer and the inner skin layers. However,the ionomer resin selected for the exterior skin layer has a lowermelting point than the ionomer resin for the inner skin layers.

[0017] In one embodiment, a weakening agent is included in the exteriorskin layer to provide peelable properties to a seal between the exteriorskin layer and itself. Such an agent weakens the seal between theexterior skin layer and itself, increasing the peelability of the seal.Examples of materials that can be used to create peelability includepolybutene, talc, ionomers in polyethylene and other incompatiblematerials in a base resin. Peelable seals through delamination,cohesive, or adhesive failure are all examples of the concept.

[0018] Additional aspects and advantages of this invention will beapparent from the following detailed description of additionalembodiments thereof, which proceeds with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is a perspective view of a foldover squeeze package with anoutlet shown in a dotted line.

[0020]FIG. 2 is a perspective view of the same package illustrated inFIG. 1 before the top portion of the package has been folded over.

[0021]FIG. 3 is a perspective of the package shown in FIG. 2 with thetop portion folded over.

[0022]FIG. 4 is a cross section view of a flap portion of the packageshown in FIGS. 1-3.

[0023]FIG. 5 is a partial, perspective view with a perforated score lineforming a tab, before the package has been folded over itself.

[0024]FIG. 6 is a partial perspective view of the package shown in FIG.5 with the tab torn open after the package has been unfolded.

[0025]FIG. 7 depicts a first film of the present invention.

[0026]FIG. 8 depicts a second film of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0027] The present invention relates to improved films for foldoversqueeze packages that are easily opened and easy to use. The improvedfilms are adapted to form squeeze packages similar to the packagesdisclosed in U.S. Patent Publication No. 2001/0030192, incorporated byreference above. The squeeze packages are designed to contain a flowablematerial and to dispense the materials in a controlled fashion. Examplesof flowable materials include condiments such as ketchup, shampoo,syrups, salad dressings, confectionery items, candy, hand cream, liquiddetergents, motor oil, toothpaste and pet food. The squeeze package iscapable of dispensing the flowable food or beverages directly into themouth of the user.

[0028] The films of the present invention are capable of forming an easyto open squeeze package without requiring localized adhesive. Thepackage is formed of a first film and a second film that are sealed toeach other around the perimeter of the pouch, forming the sidewalls ofthe pouch. The film compositions are selected so that the pouch can befolded over itself and sealed around an outlet without disrupting theseal between the two sidewalls and without sealing the sidewallstogether.

[0029] The films may be manufactured from a number of suitablethermoplastic materials and are capable of forming foldover squeezepackages in high speed packaging equipment. The packaging equipment isadapted to form several packages across a given width of film. Polymersuseful in the first and second film are defined below.

[0030] As used herein, the term “ethylene vinyl acetate copolymer” (EVA)refers to a copolymer formed from ethylene and vinyl acetate monomerswherein the ethylene derived units (monomer units) in the copolymer arepresent in major amounts by weight and the vinyl acetate in thecopolymer is present in minor amounts by weight.

[0031] As used herein, the term “ionomer” refers to ionomer classmaterials and include selected molecular weight grades of copolymerssuch as ethylene/methacrylic acid or ethylene/acrylic acid combined witha metal salt, such as zinc, sodium or lithium, then acid neutralized tocreate ion clusters. Ionomer resins available from DuPont under thetradename Surlyn are examples of suitable ionomers.

[0032] As used herein, the term “ethylene/alpha-olefin copolymer” refersto any product prepared by the copolymerization of ethylene and any oneor more alpha-olefins. Typically, the alpha-olefin is a C₃-C₂₀alpha-monoolefin, more typically, a C₄-C₈ alpha-monoolefin. In oneembodiment, the alpha-olefin may comprise at least one member selectedfrom the group consisting of 1-butene, 1-hexene, and 1-octene,respectively.

[0033] As used herein, the term “metallocene polyethylene” (mPE) refersto any polyethylene manufactured using a single site (e.g. metallocene)catalyst. Metallocene polyethylene is typically ethylene/alpha olefincopolymer.

[0034] As used herein, the phrase “low density polyethylene” (LDPE)refers to ethylene homopolymer having a density ranging from about 0.91g/cm³ to about 0.925 g/cm³. LDPE is typically produced usingconventional high pressure process.

[0035] As used herein, the phrase “linear low density polyethylene”(LLDPE) refers to ethylene alpha-olefin copolymers having a densityranging from about 0.915 g/cm³ to about 0.94 g/cm³. LLDPE can bemanufactured using a conventional Ziegler Natta catalyst or a singlesite catalyst, such as metallocene.

[0036] As used herein, the phrase “linear medium density polyethylene”(LMDPE) refers to ethylene alpha-olefin copolymers having a densityranging from about 0.925 g/cm³ to about 0.94 g/cm³. LMDPE can bemanufactured using conventional Ziegler Natta catalysts or single sitecatalysts, such as metallocene.

[0037] As used herein, the phrase “high density polyethylene” (HDPE)refers to ethylene alpha-olefin copolymers or ethylene homopolymerhaving a density of about 0.94 g/cm³ or greater. HDPE can be producedwith several classes of catalysts, such as Ziegler-Natta catalysts andmetallocene catalysts.

[0038] As used herein, the term “polybutene” refers to those polymericentities comprised of butene and another monomeric unit such asethylene, propylene, 1-hexene, 4-methyl-1-pentene, 1-octene, and1-decene units, with the butene monomeric unit comprising the majorcomponent of the copolymer. This polymer is sometimes referred to aspolybutylene.

[0039] As used herein, “ethylene vinyl alcohol copolymer” (EVOH)includes saponified or hydrolyzed ethylene vinyl acetate copolymers, andrefers to a vinyl alcohol copolymer having an ethylene comonomer. EVOHis typically prepared by, for example, hydrolysis of vinyl acetatecopolymers, or by chemical reactions with polyvinyl alcohol. The degreeof hydrolysis is typically greater than about 50% and more typicallygreater than about 85%.

[0040] As used herein, “polypropylene” refers to those polymericentities that are propylene homopolymers and propylene copolymers.Propylene copolymers comprise propylene copolymerized with a lesseramount of another monomeric unit, typically ethylene.

[0041] As used herein, the phrase “tie layer” refers to any internallayer, of a multilayer film. A tie layer may be used between two layersto adhere the two layers to one another.

[0042]FIG. 1 illustrates a perspective view of one embodiment of asqueeze package 10 with a first sidewall 30 and a second sidewall 40.The second sidewall 40 defines an outlet 20 shown in dotted lines. Thefirst and second sidewalls are joined together along three edges, filledwith liquid or other flowable product and sealed along a fourth edge.

[0043] As shown in FIG. 1, a portion or flap 50 of the squeeze packageis folded over and sealed in a peelable seal to the second sidewall ofthe package. The second sidewall is capable of adhering directly toitself to form the peelable seal. As used herein, the “directly adhered”is defined as adhesion of one film layer to itself or another filmlayer, without the use of adhesive. When access to the contents of thepackage is desired, the flap is peeled away, automatically exposing theoutlet for the flowable material.

[0044]FIG. 2 illustrates a perspective view of the squeeze package shownin FIG. 1 before the flap of the squeeze package is folded over andsealed to the second sidewall of the package. The outlet of the squeezepackage shown in FIGS. 1-3 is a hole 20 that has been punched into thesecond sidewall of the package. When a portion of the squeeze package isfolded over, the folded over portion or flap is sealed to the area ofthe second sidewall defining hole 20, as shown in FIG. 4. The flap issealed to the package sidewall so that the flap can be manually unfoldedto expose the hole.

[0045] In another embodiment, shown in FIGS. 5-6, the second sidewall 40of the package contains a fault line score pattern that forms a tab 60.In this embodiment, the flap 50 is folded over and sealed to the areainside the score pattern so that when the flap 50 is unfolded, the tabis torn away from the second sidewall 40 at the score pattern and anoutlet 20′ is created. Such score lines may be created by laser cuts andmay be made in increments of less than a thousandth of an inch deep inthin films. Alternatively, instead of being formed by perforations, thetab 60 may be cut into the sidewall. In another embodiment, the outletmay be spout. The flap may be folded over and sealed around the spout.

[0046] The first sidewall comprises a first film and the second sidewallcomprises a second film. A cross section of an embodiment of first film100 with seven layers is illustrated at FIG. 7. First film 100 includesan inner skin layer 122 that is adapted to provide an interior surfaceof the package. First film 100 further includes an exterior skin layer110 that is adapted to provide an exterior surface of a package. Thefirst film also includes five core layers 112, 114, 116, 118, 120. Whilethe first film is described as having multiple layers, the first filmmay be a single layer film containing only the inner skin layer.

[0047] A cross section of an embodiment of second film 200 with sevenlayers is illustrated at FIG. 8. The second film generally comprises atleast two layers, an exterior skin layer and an inner skin layer. Asused herein, the term exterior skin layer refers to a layer that formsan exterior surface, such as layer 210, of the squeeze package and theterm inner skin layer refers to a layer that forms an interior-facingsurface of the squeeze package, such as layer 222. The embodiment shownin FIG. 8 includes five core layers 212, 214, 216, 218, 220.

[0048] The relative sealing temperatures of resins useful in the filmsare discussed below. The melting temperatures of the resins making up afilm sealing layer determine the layer's sealing temperature. Threeconditions affect the creation of a seal: time, temperature andpressure. A film layer will begin to seal to itself when the layeritself approaches the melting temperature, but before the meltingtemperature is reached. Thus the sealing temperature is a temperature ator below the melting temperature. However, note that to create a seal ina desired amount of time, the manufacturing equipment may be set at atemperature setting higher than the sealing temperature. It may also bedesirable to allow the sealing layer to reach a temperature about 10° F.to about 20° F. above the sealing temperature to ensure a complete seal.For embodiments in which it is desirable to “overshoot” the sealingtemperature in this manner, materials for the inner skin layers and theexterior skin layer should be selected to provide the exterior skinlayer with a sealing temperature of at least about 20° F. to about 30°F. less than the sealing temperature of the inner skin layers. Theresins appropriate for use in the exterior skin layer and the inner skinlayers are discussed in more detail below.

[0049] The composition of the inner skin layer of the first film and thecomposition of the inner skin layer of the second film are selected toallow the inner skin layers to be heat sealed together in a permanentseal on packaging equipment. The inner skin layers are sealed around theperimeter of the sidewalls to form the package. The temperature forsealing the inner skin layers together is referred to herein as thesidewall sealing temperature or first sealing temperature. In oneembodiment, the first sealing temperature ranges from about 200° F. (93°C.) to about 280° F. (138° C.). In another embodiment, the first sealingtemperature ranges from about 210° F. (99° C.) to about 280° F. (138°C.).

[0050] In one embodiment, the compositions of the inner skin layers areidentical. Alternatively, the inner skin layers may have compositionsthat differ from each other as long as the layers are heat sealable toeach other at the desired temperature. The inner skin layers may containthermoplastic polymers such as ionomer, ethylene vinyl acetate,polypropylene, ethylene/alpha olefins, copolymer polyester and blendsthereof. Suitable ionomer resins include those available from Dupont,under the tradename Surlyn, such as product numbers 1857, AD9464-3,1705, 1650, 1652 and 1601. Suitable ethylene/alpha olefin resins includeLDPE, mPE, LDPE, LLDPE, and LMDPE. In one embodiment, the inner skinlayers comprise LLDPE with a melt index ranging from about 0.5 to about6.0. LLDPE resins with a high melting temperature can be selected. Forexample, commonly available LLDPE resins melt at about 250° F. orhigher. These resins are useful in embodiments in which it is desirableto have the inner skin layers seal at a temperature over 20° F. greaterthan the sealing temperature of the exterior skin layer.

[0051] In another embodiment, the inner skin layers comprise ionomerwith melt index ranging from about 0.5 to about 6.0. Examples ofsuitable LLDPE resins include those available from Dow Chemical Company(“Dow”) under the tradename Dowlex, such as product numbers 2045G, 2256Hand 2056G, and those available from Huntsman under the tradename REXell,such as product number 8101. Another suitable LLDPE resin is availablefrom Nova under the tradename NOVAPOL. LDPE with a melt index rangingfrom about 0.5 g/10 minutes to about 6.0 g/10 minutes may alternativelybe used for the inner skin layers. Suitable examples of LDPE resinsinclude those available from Equistar under the tradename PetrotheneM2520; those available from CPChem under the tradename Marlex orMarflex; those available from Eastman under the tradenames HIFOR andMXSTEN. An example of a suitable mPE resin is the resin available fromDow under the tradenames and product numbers Affinity PL1850 and Elite5100G. Other suitable mPE resins are sold by Exxon Mobil under thetradenames and product numbers Exact 3132 and 3131 and Exceed 1018CA.Suitable polypropylene polymers include propylene homopolymer andcopolymers having a melt index ranging from about 3 g/10 minutes toabout 12 g/10 minutes. Examples of suitable polypropylene copolymerresins for use in the inner skin layers are the resins available fromMontel under the tradename SA861 and from Exxon under the tradename andproduct number Escorene PD9012E1. Inner skin layers containingpolypropylene may also contain additives, such as the additive availablefrom Ampacet under the product number 701402. Suitable copolymerpolyester resins include those sold by Eastman under the tradenameEastobond and those sold by Dupont.

[0052] The exterior skin layer or second layer of the second film isadapted for use as an exterior surface of the squeeze package. Inaddition, the exterior skin layer has a composition that permits thelayer to seal to itself to form a peelable seal. As used herein apeelable seal refers to a seal that is sufficiently weak to be peeledapart manually but remains intact during storage and until ready foruse. A peelable seal is generally a seal that can be peeled apart withthe application of force equal to less than three pounds per linearinch. The exterior skin layer further comprises a composition that iscapable of forming this peelable seal at a temperature below thesidewall sealing temperature so that the peelable seal may be formedwithout affecting the integrity of the seal between the first and secondsidewalls and without sealing the sidewalls to each other.

[0053] The exterior skin layer comprises a heat activated resin. Theexterior skin layer may also comprise a weakening agent, such aspolybutene, to give the peelable seal the desired peelability. In oneembodiment, the exterior skin layer has a composition that enables thelayer to seal with itself at a temperature that is at least about 8° F.(4° C.) below the sidewall sealing temperature. In another embodiment,the exterior skin layer is capable of forming a seal with itself at atemperature that is at least about 20° F. less than the sidewall sealingtemperature. In another embodiment, the heat activated resin forms aseal at a temperature that is at about 30° F. (10° C.) to about 100° F.(16° C.) less than the sidewall sealing temperature. In one embodiment,the exterior skin layer seals to itself at a temperature that is atleast about 30° F. (17° C.) less than the sidewall sealing temperature.In yet another embodiment, the exterior skin layer has a compositionselected to enable the exterior skin layer to seal to itself at atemperature at least about 50° F. (28° C.) less than the sidewallsealing temperature. The seal is typically formed between two portionsof the exterior skin layer at temperatures ranging from about 150° F.(66° C.) to about 260° F. (127° C.). The specific sealing temperaturedepends on the composition of the exterior skin layer.

[0054] Suitable heat activated resins include EVA, LDPE, mPE, LLDPE,ethylene acrylic acid, polyethylene, ethylene methacrylic acid,polypropylene or blends thereof. Ionomer is a preferred polymer for useas a heat activated resin in the exterior skin layer. Ionomer with amelt index ranging from about 0.5 g/10 minutes to about 6.0 g/10 minutesmay be used in the exterior skin layer. Suitable examples of ionomerinclude those discussed above in connection with the exterior layer. EVAcopolymer resin containing between 4.5 and 23% by weight vinyl acetatewith a melt index ranging from about 0.5 g/10 minutes to about 6.0 g/10minutes may be used in the exterior skin layer. Suitable examples of EVAresins include those available from Dupont under the tradenames Elvax3170 and 3169 and those available from Equistar under the tradename720.01. Polypropylene having a melt index ranging from about 3 g/10minutes to about 12 g/10 minutes may be used in the exterior skin layer.Examples of suitable polypropylene resins include those discussed abovein connection with the inner skin layers.

[0055] As mentioned above, the exterior skin layer composition isselected to seal to itself at a temperature below the sidewall sealingtemperature. In embodiments of the films where the inner skin layerscomprise LLDPE with a seal temperature of about 252° F. (122° C.),examples of suitable polymer resins for the exterior skin layer in thisembodiment include: ionomer, a blend of ionomer and polybutene a blendof EVA and polybutene; and a blend of ionomer, EVA and polybutene. Anexterior skin layer comprising a blend of EVA and polybutene forms apeelable seal at about 185° F. (85° C.). An exterior skin layercomprising ionomer or a blend of ionomer, EVA and polybutene forms apeelable seal at about 200° F. (93° C.). A blend of ionomer and withpolybutene forms a peelable seal at about 190° F.

[0056] In one embodiment, the inner skin layers comprise LLDPE with amelt index ranging from about 0.5 to about 6.0 and which seals at atemperature of about 252° F. The exterior skin layer comprises about 90%ionomer, 5% polybutene, 5% slip/antiblock additive and seals at atemperature of about 190° F.

[0057] For an inner skin layer of LDPE with a melt index ranging fromabout 0.5 to about 6.0, which seals at a temperature of 225° F. (107°C.), examples of suitable polymer resins for the exterior skin layerinclude ionomer, EVA, and mPE with a melt index ranging from about 0.5to about 6.0. Each of these polymers is selected to have a sealingtemperature below about 210° F. (99° C.).

[0058] For an inner skin layer of ionomer with a melt index ranging fromabout 0.5 to about 6.0 which seals at a temperature of 208° F. (98° C.),examples of suitable polymer resins for the exterior skin layer includeionomer, EVA and mPE, each having a melt index ranging from about 0.5 toabout 6.0 and a sealing temperature about 10° F. to about 20° F. lessthan the sealing temperature of the sidewall sealing temperature.

[0059] As discussed above, the exterior skin layer may further containany weakening agent known in the art to weaken a film layer, so that aseal between the exterior skin layer and itself has the desired level ofpeelability. As discussed above, the seal is sufficiently weak so thatit may be manually pulled apart, but sufficiently strong so that itremains intact during storage and shipping. Suitable examples ofweakening agents include polybutene, talc, ionomers, mica, silica andpolypropylene. For example, the exterior skin layer could comprise anyof the following: ionomer blended with ethylene polymer; ionomer withethylene copolymers such as ethylene vinyl acetate, ethylenemethylacrylate, and polybutene with polyethylene, mPE, ethylenecopolymers or ionomer; polypropylene blended into polyethylene, mPE orpolyethylene copolymers; any one of talc, mica or silica blended intoionomer, polyethylene, mPE, or ethylene copolymers. In one embodiment,the exterior skin layer contains an amount of polybutene ranging fromabout 3% to about 30% by weight of the exterior skin layer. Inembodiments with an exterior skin layer containing ionomer, the exteriorskin layer may contain polybutene in an amount up to about 15% by weightof the exterior skin layer. In embodiments with an exterior skin layercontaining EVA, the exterior layer may contain polybutene in an amountranging from about 10% to about 30% by weight. In another embodiment,the exterior skin layer contains EVA in an amount ranging from about 15%to about 20% by weight of the layer.

[0060] Suitable examples of polybutene resins include polybutene-1 suchas those available from Basell under the tradenames PB1600SA and PB8640.The exterior skin layer may further contain additives such as antiblock,slip and other additives known in the art.

[0061] The first film and second film may have additional layers thatare positioned as core layers. The compositions of the additional corelayers depend on the properties desired for the squeeze package. Forexample, the first and second films may have one or more layers of amaterial such as EVOH, polypropylene homopolymer, polypropylenecopolymer, HDPE, MDPE, polyamide (nylon), polyester (“PET”),polyvinylidene chloride (“PVDC”) and liquid crystalline polymer. An EVOHlayer may be used to provide the film with oxygen barrier properties.One or more polypropylene layers may be used provide the film withmoisture barrier properties. HDPE or MDPE layers may be used to providestiffness. Polyamide or polyester layers may be used to provide the filmwith toughness and oxygen barrier properties. PVDC or liquid crystallinelayers may be used provide moisture and oxygen barrier properties. Otherproperties may also be obtained through such layers. Examples ofsuitable HDPE resins include those available from CPChem under thetradename Marlex LX2419, 9662, 9659; and those available from Equistarunder the tradenames Alathon M6210, L15885, M6020. Examples of suitableEVOH resins include those available from Nippon Gohsei under thetradenames Soarnol DC3203F and ET 3803; and those available from EvalCompany of America under the tradenames F101B and H101B. An example of apolypropylene homopolymer resin suitable for a barrier layer includesthe resin available from Amoco under the tradename 10-6721, with a meltindex of 7.0 g/10 minutes and a density of 0.900 g/cm³. If polypropyleneis used in the barrier layer, the barrier layer may also contain a smallamount of additive, such as clarifying agents, slip additive, antiblockor other additives know in the art. An example of a suitable additive isthe additive available from Milliken under the tradename 8C41-10. In oneembodiment, the barrier layer contains additive in an amount less thanabout 10% by weight of the barrier layer. In another embodiment, thebarrier layer contains additive in an amount less than about 5% byweight of the barrier layer.

[0062] In addition, the first film may also have an exterior-facingsurface layer of polymers such as HDPE, MDPE, polypropylene, PET orpolyamide to enable the film to receive printing.

[0063] One or more of the layers in each film may contain whiteconcentrate such as TiO₂. In embodiments of the films containing HDPElayers, the white concentrate may be included in each HDPE layer in anamount ranging up to about 40% by weight of the HDPE layer. Whiteconcentrate provides the film with light barrier properties. Whiteconcentrates are typically loaded with up to about 90% by weighttitanium dioxide. Suitable white concentrates include those availablefrom Ampacet under the tradename 110359. The film may also contain otherconcentrates known to provide alternate colors or light barriers, suchas red color or black for light barrier.

[0064] The first and second film may further include tie layers toadhere two layers to one another. For films containing polyethylene,suitable tie layer materials include maleic anyhydride graftedpolyethylene, anhydride grafted ethylene vinyl acetate and LLDPE basedmaleic anhydride grafted polyethylene. Suitable resins for use in thetie layers include those available from Dupont under the tradenamesBynel 4104 and 41E529; and those available from MSI under the tradenamePlexar 360E. In the case of a film containing a barrier layer ofpolypropylene homopolymer, a suitable tie layer may be a layer ofpolypropylene copolymer, such as the resin available from Fina under thetradename Z9470. In addition, the first film may have an exterior-facingsurface layer of HDPE or polypropylene to enable the film to receiveprinting.

[0065] The inventive films may have any thickness suitable for thedesired properties of the film. Films used in packages containing aflowable product, typically have a thickness ranging from about 1 mil(25 micron) to about 4 mils (102 micron), more typically from about 2mils (51 micron) to about 3 mils (76 micron). The skin layers shouldhave sufficient thickness to provide the desired sealing strength anduniformity. In one embodiment, the skin layers have thickness of atleast about 0.1 mil (2.5 microns). In another embodiment, the skinlayers have a thickness of about 0.6 mil (15 micron). Each skin layermay comprise at least about 5% of the total film thickness. For example,in an embodiment of the second film with seven layers, with film layersrepresented by the construction A/B/C/D/E/F/G, the film layers havecorresponding percentage thicknesses as follows: 20/20/6/10/6/15/23.

[0066] The films in accordance with the present invention can bemanufactured using film fabrication technologies well-known in the art.For example, all of the film layers may be coextruded using cast film orblown film manufacturing techniques. Alternatively, the exterior skinlayer may be formed by solvent deposition or lamination or lamination tothe film. However, one method of manufacture of the multilayer film ofthe present invention is via simultaneous coextrusion, of all the layersof the multilayer film.

[0067] The films in accordance with the present invention can be use toform foldover squeeze packages without any additional adhesive appliedto the film. The films are also capable of forming a package with asidewall that can be peelable sealed to itself without disrupting theintegrity of the package itself.

EXAMPLES Example 1

[0068] A sample package was prepared from two films, each with sevenlayers coextruded in a blown film process. The second film had a filmconstruction as identified below in Table A. TABLE A % % By Wt. of MeltLayer Thickness Polymer Type Layer Index Density A 20.0% ionomer 90.0%1.6 0.950 slip/antiblock 5.0% 25.0 0.960 Polybutene 5.0% 1.0 0.910 B20.0% HDPE 65.0% 1.0 0.963 white concentrate 35.0% 1.6 2.030 C 6.0%LLDPE-maleic 100%.0% 2.0 0.925 anhydride D 10.0% EVOH 32% 100.0% 3.21.190 E 6.0% LLDPE-maleic 100.0% 2.0 0.925 anhydride F 15.0% 65.0% 1.00.963 white concentrate 35.0% 1.6 2.030 G 23.0% LLDPE 77.0% 1.0 LDPE20.0% 2.0% 0.925 slip/antiblock 3.0% 1.080

[0069] The first film had a film construction that was the same as theconstruction described above for the second film, except that the Alayer of the second film comprised 65% by weight of HDPE and 35% byweight white concentrate.

[0070] A package was prepared from the two films, with the LLDPE layers(the G layers) of the first and second films sealed together at 252° F.(122° C.) to create first and second sidewalls. This seal was permanentand would not peel without tearing the film. The second sidewallcontained an outlet aperture that was closed off by a flap. The flap wasa folded over portion of the package and a peelable seal was createdaround the outlet aperture by sealing the ionomer/polybutene layer (Alayer) of the second sidewall to itself. The peelable seal was formed at190° F. (88° C.) and did not affect the seal between the sidewalls ofthe package. The peelable seal formed by the second film peeled with theapplication of less than 2.5 lbs/in (0.43 kg/cm). The peelable seal ofthe second sidewall provided good retention of seal strength over time.

Example 2

[0071] A package was prepared of two films, each with seven layerscoextruded in a blown film process. The first film was the same as thefirst film identified for Example 1. The second film was the same as thesecond film identified in Example 1 except that the A layer comprised56% ionomer, 33% EVA, 6% slip/antiblock and 5% polybutene. The packagewas prepared as described above in Example 1.

[0072] The LLDPE layers of the first and second films were sealedtogether at 252° F. (122° C.) to create first and second sidewalls. Theseal between the LLDPE layers was sufficiently strong that it would notpeel without tearing the film. The second sidewall contained an outletaperture that was closed off by a flap. The flap was a folded overportion of the package and a peelable seal was created around theoutlet. The second film formed this seal at a temperature of about 190°F. (93° C.) without affecting the integrity of the seal between theLLDPE layers. The peelable seal formed by the second film peeled withthe application of less than 2.5 lbs/in (0.43 kg/cm). The peelable sealof the second sidewall provided good retention of seal strength overtime.

Example 3

[0073] A package was prepared of two films, each with seven layerscoextruded in a blown film process. The first film was the same as thefirst film identified for Example 1. The second film was the same as thesecond film identified in Example 1 except that the A layer comprisedionomer. The package was prepared as described above in Example 1.

[0074] The LLDPE layers of the first and second films were sealedtogether at 252° F. (122° C.) to create first and second sidewalls. Theseal between the LLDPE layers was sufficiently strong that it would notpeel without tearing the film. The second sidewall contained an outletaperture that was closed off by a flap. The flap was a folded overportion of the package and a peelable seal was created around theoutlet. The second film formed this seal at a temperature of about 200°F. (93° C.) without affecting the integrity of the seal between theLLDPE layers. The peelable seal formed by the second film peeled withthe application of less than 2.5 lbs/in (0.43 kg/cm). The peelable sealof the second sidewall provided good retention of seal strength overtime.

Example 4

[0075] A package was prepared of two films, each with seven layerscoextruded in a blown film process. The first film was the same as thefirst film identified for Example 1. The second film was the same as thesecond film identified in Example 1 except that the A layer comprisedEVA and polybutene. The package was prepared as described above inExample 1.

[0076] The LLDPE layers of the first and second films were sealedtogether at 252° F. (122° C.) to create first and second sidewalls. Theseal between LLDPE layers was permanent would not peel without tearingthe film. The second film was directly sealed to itself in a peelableseal at a temperature of 185° F. (85° C.) without affecting theintegrity of the seal between the LLDPE layers. The peelable seal formedby the second film peeled with the application of less than 2.5 lbs/in(0.43 kg/cm). The peelable seal of the second sidewall providedsufficient retention of seal strength over time for closing off theoutlet aperture during storage and shipping.

Example 5

[0077] A package was prepared of two films prepared in a cast filmprocess. The compositions and structure of the two film are described inTables A and B. As used in Tables A and B, clarifying agent refers to anadditive available from Milliken Chemical under the tradename 8C41-10and slip additive refers to an additive available from Ampacet under theproduct number 7012402. The first film had the structure and compositionas identified below in Table B. TABLE B % % By Wt. of Layer ThicknessPolymer Type Layer Melt Index Density A 25.0% polypropylene 99 7.0 0.906clarifying agent 1 B   50% polypropylene 99 1.0 0.963 clarifying agent1.0% 1.6 2.030 C 25.0% MPE 92.8 3.0 0.902 polypropylene 3.2 6.0 0.900slip additive 2.2 4.0 0.919

[0078] The second film had the structure and composition identifiedbelow in Table C. TABLE C Layer Percent of Resin Layer Percent PolymerType Layer Melt Index Density A 20.0% 18% EVA 70.0 1.5 0.940 Polybutene15.0 4.0 0.908 Polypropylene 15.0 6.0 0.900 B 5.0% Polypropylene 100.0%5.0 0.890 C 50.0% Polypropylene 99.0% 7.0 0.900 clarifying agent 1.00.900 D 25.0% MPE 92.8 3.0 0.906 Polypropylene 3.2 6.0 0.900 slipadditive 4.0% 2.2 0.919

[0079] The first film and the second film were oriented so that the Clayer of the first film and the D layer of the second film werepositioned adjacent to each other. The C layer of the first film and theD layer of the second film were sealed to each other to form a perimeterof a package at a temperature of about 207° F. (97° C.). The package wasfolded over itself and so that the A layer sealed to itself. The A layerformed a peelable seal with itself at a temperature of about 185° F.(85° C.). The peelable seal of the second sidewall provided sufficientretention of seal strength over time for closing off the outlet apertureduring storage and shipping.

[0080] It will be obvious to those having skill in the art that manychanges may be made to the details of the above-described embodiments ofthis invention without departing from the underlying principles thereof.The scope of the present invention should, therefore, be determined onlyby the following claims.

1. Films for forming a foldover squeeze package used to contain flowablematerials such as condiments, wherein the package has a first sidewalland a second sidewall that are sealed to each other around theirrespective perimeters, wherein the second sidewall has an outlet thatpermits the flowable material to exit the package and wherein a portionof the package is folded over so that the second sidewall is sealed toitself around the outlet; the films comprising: a first film for forminga first sidewall of a squeeze package, the first film having at least aninner skin layer providing an inner facing surface adapted for use as aninterior surface of a first sidewall of a squeeze package, a second filmfor forming a second sidewall of a squeeze package, the second filmhaving at least two layers, including an inner skin layer that isadapted for use as an interior surface of a second sidewall of a squeezepackage and an exterior skin layer that is adapted for use as anexterior surface of a second sidewall of a squeeze package, wherein theexterior skin layer contains a heat activated resin, wherein the innerskin layer of the second film is capable of sealing at its surface tothe inner skin layer of the first film at a first sealing temperature toform a perimeter of a squeeze package, wherein the exterior skin layerof the second film, when sealed directly to itself, is capable offorming a peelable seal at a second sealing temperature below the firstsealing temperature without affecting the integrity of the seal betweenthe first and second sidewalls, wherein the exterior skin layer layer,when sealed to itself at a second temperature, forms a peelable sealthat is sufficiently weak to be peeled apart manually and that issufficiently strong to remain sealed during storage and until ready foruse.
 2. The films as claimed in claim 1, wherein the heat activatedresin comprises at least one polymer selected from the group consistingof polypropylene, ethylene/alpha olefin, ethylene vinyl acetate,ethylene methylacrylate copolymer, polyethylene, ethylene methyl acrylicacid and blends thereof.
 3. The films as claimed in claim 1, wherein theheat activated resin comprises ionomer.
 4. The films as claimed in claim1, wherein the exterior skin layer of the second film contains aweakening agent.
 5. The films as claimed in claim 4, wherein theweakening agent is selected from the group consisting of ionomer blendedwith polyethylene; ionomer with ethylene vinyl acetate; ionomer blendedwith ethylene methylacrylate; polypropylene blended with polyethylene;talc; mica; and silica.
 6. The films as claimed in claim 4 wherein theweakening agent is polybutene.
 7. The films as claimed in claim 1wherein the exterior skin layer contains polybutene in amount rangingfrom about 3% to about 30% by weight of the exterior skin layer.
 8. Thefilms as claimed in claim 1, wherein the inner skin layer of the firstfilm comprises the same composition as the inner skin layer of thesecond film.
 9. The film as claimed in claim 1, wherein the inner skinlayer comprise linear low density polyethylene.
 10. The films as claimedin claim 1, wherein the inner skin layers comprise at least one polymerselected from the group consisting of ionomer, low density polyethylene,linear low density polyethylene, linear medium density polyethylene,metallocene catalyzed polyethylene and copolymer polyester.
 11. Thefilms as claimed in claim 1, wherein the second sealing temperature isat least about 8° F. below the first sealing temperature.
 12. The filmsas claimed in claim 1, wherein the second sealing temperature is atleast about 20° F. below the first sealing temperature.
 13. The films asclaimed in claim 1, wherein the second sealing temperature is at leastabout 30° F. below the first sealing temperature.
 14. The films asclaimed in claim 1, wherein the second sealing temperature is at leastabout 50° F. below the first sealing temperature.
 15. The films asclaimed in claim 1, wherein the first sealing temperature ranges fromabout 200° F. to about 280° F. and the second sealing temperature rangesfrom about 150° F. to about 260° F., wherein the second temperature isat least about 20° F. below the first sealing temperature.
 16. The filmsas claimed in claim 1, wherein the inner skin layers comprise linear lowdensity polyethylene and wherein the exterior skin layer comprises apolymer blend selected from the group consisting of: a blend of ethylenevinyl acetate and polybutene; and a blend ethylene vinyl acetate andpolybutene.
 17. The films as claimed in claim 1, wherein the inner skinlayers comprise linear low density polyethylene and wherein the exteriorskin layer comprises ionomer.
 18. The films as claimed in claim 1,wherein the inner skin layer comprise linear low density polyethyleneand wherein the exterior skin layer comprises a blend of ionomer andpolybutene.
 19. The films as claimed in claim 1, wherein the inner skinlayers comprise ionomer and wherein the exterior skin layer comprises apolymer or polymer blend selected from the group consisting of: ionomer;and a blend of ethylene vinyl acetate and metallocene catalyzedpolyethylene.
 20. The films as claimed in claim 1, wherein the innerskin layers comprise a blend metallocene catalyzed polyethylene andpolypropylene and the exterior skin layer comprises a blend of EVA,polybutene and polypropylene.
 21. The films as claimed in claim 1,wherein the inner skin layers comprise a blend of LLDPE and LDPE and theexterior skin comprises layer a blend of ionomer and ethylene vinylacetate.
 22. The films as claimed in claim 1, wherein the inner skinlayers comprise low density polyethylene and wherein the exterior skinlayer comprises a polymer or polymer blend selected from the groupconsisting of: ionomer and a blend of ethylene vinyl acetate andmetallocene catalyzed polyethylene.
 23. The films as claimed in claim 1,wherein the inner skin layers comprise a blend of linear low densitypolyethylene and low density polyethylene
 24. The films as claimed inclaim 1, wherein the films further comprise at least one core layer. 25.The films as claimed in claim 20, wherein the core layer comprises apolymer selected from the group consisting of: ethylene vinyl alcoholcopolymer; polypropylene homopolymer; polypropylene copolymer; highdensity polyethylene; medium density polyethylene; polyamide; polyester;polyvinylidene chloride; and liquid crystalline polymer.
 26. The filmsas claimed in claim 1, wherein the peelable seal can be pulled apartwith the application of force of less than about three pounds per linearinch.
 27. A foldover squeeze package used to contain flowable materialssuch as condiments, comprising: a first film sidewall with at least onefilm layer, including an inner skin layer that forms an interior surfaceof the package, a second film sidewall with at least two layers,including an inner skin layer that forms an interior surface of thesqueeze package and an exterior skin layer that forms an exteriorsurface of the squeeze package, wherein the inner skin layer of thesecond film sidewall is capable of sealing at its surface to the innerskin layer of the first film sidewall at a first sealing temperature toform a perimeter of a squeeze package, wherein the exterior skin layerof the second film sidewall contains a heat activated resin and iscapable of sealing to itself in a peelable seal at a second sealingtemperature below the first sealing temperature without affecting theintegrity of the seal between the first and second film sidewalls,wherein the exterior skin layer, when sealed to itself at a secondtemperature, forms a peelable seal that is sufficiently weak to bepeeled apart manually and that is sufficiently strong to remain sealedduring storage and until ready for use, wherein the inner skin layers offirst and second film sidewalls are adhered to each other along theperimeter of the package, and wherein the second sidewall defines anoutlet adapted to permit flowable material to exit the package in acontrolled fashion; wherein a flap of the package is folded over andsealed to itself in a peelable seal around the outlet, wherein thepeelable seal is located between the exterior skin layer of the secondsidewall and itself.
 28. The foldover squeeze package as recited inclaim 27, wherein the outlet comprises a tab defined by a score linethat is adapted to be torn away from the second sidewall to open thepackage when the flap is pulled open.
 29. The foldover squeeze packageas recited in claim 27 wherein the outlet is an opening cut in thesecond sidewall.
 30. The foldover squeeze package as recited in claim27, wherein the heat activated resin comprises at least one polymerselected from the group consisting of: ionomer; polypropylene;ethylene/alpha olefin; ethylene vinyl acetate; ethylene methylacrylatecopolymer; polyethylene; ethylene methyl acrylic acid and blendsthereof.
 31. The foldover squeeze package as recited in claim 27 whereinthe exterior skin layer of the second film contains a weakening agent.32. The foldover squeeze package as recited in claim 31, wherein theweakening agent is selected from the group consisting of ionomer blendedwith polyethylene; ionomer with ethylene vinyl acetate; ionomer blendedwith ethylene methylacrylate; polypropylene blended with polyethylene;talc; mica; and silica.
 33. The foldover squeeze package as recited inclaim 31, wherein the weakening agent is polybutene.
 34. The foldoversqueeze package as recited in claim 27, wherein the second sealingtemperature is at least about 20° F. below the first sealingtemperature.
 35. The foldover squeeze package as recited in claim 27,wherein the peelable seal can be pulled apart with the application offorce of less than about three pounds per linear inch.
 36. The foldoversqueeze package as recited in claim 27, wherein the inner skin layer thefirst film sidewall has same composition as the inner skin layer of thesecond film sidewall.
 37. A method of forming a foldover squeeze packageused to contain flowable materials such as condiments, the methodcomprising: providing a first film with a first surface adapted for useas an interior surface of a first sidewall of a squeeze package,providing a second film with a first surface adapted for use as aninterior surface of a second sidewall of a squeeze package, the secondfilm having at least two layers, wherein the first layer is adapted foruse an interior surface of a second sidewall of a squeeze package andthe second layer is adapted for use as an exterior surface of a secondsidewall of a squeeze package, forming an outlet in the second film,wherein the outlet is adapted to allow the flowable material to exit thesqueeze package, sealing the first surfaces of the first and secondfilms together to define the perimeter of the package at a first sealingtemperature, forming a peelable seal between opposing portions of thesecond film around the outlet by folding a flap of the package over theoutlet and sealing the flap of the package over the outlet and applyingheat at a second sealing temperature below the first temperature,wherein the peelable seal is sufficiently weak to be peeled apartmanually to expose the outlet and is sufficiently strong to remainsealed during storage and until ready for use.
 38. The method as recitedin claim 37, wherein the second sealing temperature is at least about20° F. below the first sealing temperature.
 39. The method as recited inclaim 37, wherein the peelable seal can be pulled apart with theapplication of force of less than about three pounds per linear inch.